1. Field of the Invention
The present invention relates to a semiconductor device fabricating method including a process for forming a wiring layer, an interlayer film and an opening and a process for cleaning the opening and a treating liquid used in cleaning of the opening. More specifically, the present invention relates to a semiconductor device fabricating method which may prevent elusion and oxidation of the Wiring layer in a cleaning process after forming at least one of the interlayer film and the opening under a plasma atmosphere and a treating liquid used in cleaning of the opening. The present application is based on Japanese Application No. 2001-212191 and No. 2002-197948, which is incorporated herein by reference.
2. Description of the Related Art
A semiconductor device is fabricated by forming on a semiconductor substrate an interlayer film, a wiring layer made of metal such as Cu, and an opening of the interlayer film by methods such as sputtering, dry etching and plasma ashing. Thereafter, the semiconductor device is cleaned with an organic release liquid to remove contamination such as an etching residue produced when the interlayer film, the wiring layer and the opening are formed. For example, an amine release liquid is used as the organic release liquid.
This will be described by using a flowchart showing a semiconductor device cleaning method with the organic release liquid shown in FIG. 22. FIG. 22 shows a process for forming a via in an interlayer film on a wiring made of Cu (hereinafter, referred to as a Cu wiring), which is reaching the Cu wiring to fabricate a semiconductor device, followed by a semiconductor device cleaning process. As shown in step S51 of FIG. 25, the via reaching the Cu wiring is formed in an interlayer film on the Cu wiring by dry etching. Thereafter, the semiconductor device is cleaned in the process shown in steps S52 to S55.
As shown in step S52, an organic release process is performed with an amine solvent to remove an etching residue produced in step S51. At this time, under conditions of the organic release process, for example, the temperature is 70° C. and time is 10 minutes. As shown in step S53, the semiconductor device is rinsed with pure water or CO2 gas-containing water (hereinafter, referred to as CO2 water). At this time, rinse conditions are 15 minutes at room temperature. As shown in step S54, the semiconductor device is dried. The semiconductor device is dried by jetting heated N2 gas to the semiconductor device for 10 minutes.
The inventors of the present invention, however, have revealed that washing steps cause problems as described below. In rinsing with the pure water or CO2 water (hereinafter, generically referred to as pure water) shown in step S53 of FIG. 22, the Cu wiring exposed into the via is eluted into the pure water or CO2 water. Otherwise, after drying, the Cu wiring in the via is easily oxidized. The present invention has been made in view of such problems and the present invention is a semiconductor device fabricating method including a process for forming a wiring layer on a semiconductor substrate, followed by cleaning, which may prevent elution and oxidation of the wiring layer, and a treating liquid used in this fabricating method.